package utils

import (
	"github.com/gin-gonic/gin"
	"net/http"
)

// Cors 开放所有接口的OPTIONS方法
// 解决浏览器发送预检头请求
func Cors() gin.HandlerFunc {
	//return func(c *gin.Context) {
	//	method := c.Request.Method               //请求方法
	//	origin := c.Request.Header.Get("Origin") //请求头部
	//	var headerKeys []string                  // 声明请求头keys
	//	for k, _ := range c.Request.Header {
	//		headerKeys = append(headerKeys, k)
	//	}
	//	headerStr := strings.Join(headerKeys, ", ")
	//	if headerStr != "" {
	//		headerStr = fmt.Sprintf("access-control-allow-origin, access-control-allow-headers, %s", headerStr)
	//	} else {
	//		headerStr = "access-control-allow-origin, access-control-allow-headers"
	//	}
	//	if origin != "" {
	//		origin := c.Request.Header.Get("Origin")
	//		c.Header("Access-Control-Allow-Origin", origin)                                    // 这是允许访问所有域
	//		c.Header("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE,UPDATE") //服务器支持的所有跨域请求的方法,为了避免浏览次请求的多次'预检'请求
	//		//  header的类型
	//		c.Header("Access-Control-Allow-Headers", "Authorization, Content-Length, X-CSRF-Token, Token,session,X_Requested_With,Accept, Origin, Host, Connection, Accept-Encoding, Accept-Language,DNT, X-CustomHeader, Keep-Alive, User-Agent, X-Requested-With, If-Modified-Since, Cache-Control, Content-Type, Pragma")
	//		//              允许跨域设置                                                                                                      可以返回其他子段
	//		c.Header("Access-Control-Expose-Headers", "Content-Length, Access-Control-Allow-Origin, Access-Control-Allow-Headers,Cache-Control,Content-Language,Content-Type,Expires,Last-Modified,Pragma,FooBar") // 跨域关键设置 让浏览器可以解析
	//		c.Header("Access-Control-Max-Age", "172800")                                                                                                                                                           // 缓存请求信息 单位为秒
	//		c.Header("Access-Control-Allow-Credentials", "true")                                                                                                                                                   //  跨域请求是否需要带cookie信息 默认设置为true
	//		c.Set("content-type", "application/json")                                                                                                                                                              // 设置返回格式是json
	//	}
	//
	//	//放行所有OPTIONS方法
	//	if method == "OPTIONS" {
	//		c.JSON(http.StatusOK, "Options Request!")
	//	}
	//	// 处理请求
	//	c.Next() //  处理请求
	//}
	return func(c *gin.Context) {
		method := c.Request.Method
		c.Header("Access-Control-Allow-Origin", c.GetHeader("Origin"))
		c.Header("Access-Control-Allow-Headers", "Content-Type,AccessToken,X-CSRF-Token, Authorization, Token,X-Token,X-User-Id")
		c.Header("Access-Control-Allow-Methods", "POST, GET, OPTIONS,DELETE,PUT")
		c.Header("Access-Control-Expose-Headers", "Content-Length, Access-Control-Allow-Origin, Access-Control-Allow-Headers, Content-Type")
		c.Header("Access-Control-Allow-Credentials", "true")

		// 放行所有OPTIONS方法
		if method == "OPTIONS" {
			c.AbortWithStatus(http.StatusOK)
		} else {
			// 处理请求
			c.Next()
		}
	}
}
